Naphtholactam-(1,8) basic dyestuffs

ABSTRACT

ARE SUITABLE FOR THE DYEING, PRINTING AND BULK DYEING OF SYNTHETIC AND SEMISYNTHETIC MATERIALS ESPECIALLY POLYAMIDES, ACETATE RAYON AND ACID MODIFIED POLYESTERS, LEATHER, COCOA FIBERS, PAPER AND JUTE, FOR THE PRODUCTION OF INKS AND PASTE FOR BALL POINT PENS, FOR USE IN OFFSET PRINTING, FOR USE IN DYEING, PRINTING AND BULK DYEING MATERIALS WHICH COMPLETELY OR PREDOMINATELY CONSIST OF POLYMERIZED ACRYLONITRILE AND OR VINYLIDENE CYANIDE, THE DYEINGS AND PRINTS ON THE LAST MENTIONED MATERIALS ARE CHARACTERIZED BY OUTSTANDING FASTNESS PROPERTIES, ESPECIALLY FASTNESS TO LIGHT, WET PROCESSING, CROSS DYEING, DECATIZING, SUBLIMATION, EXHAUST FUMES AND RUBBING. The dyestuffs are readily soluble, they yield deep dyeings, due to their high yield and very good drawing power and they do not soil wool. In the formula given above A denotes the residual members of a heterocyclic five or six membered ring to which further rings may be annelated, R is hydrogen, alkyl aralkyl, cycloalkyl or aryl, and R may also be linked to A or to another ring which is annelated to the ring containing A, R1 is hydrogen, alkyl, aralkyl, cycloalkyl or aryl and R1 may also be linked to B or B1, and X is an anion.   Basic dyestuffs of the formula

United States Patent Brack 1 June 27, 1972 [54] NAPIITHOLACTAM-(l,8) BASIC DYESTUFFS [72] Inventor: Alfred Brack, Leverkusen, Germany Farbenfabriken Bayer Aktiengesellschaft, Leverkusen, Germany 22 Filed: :Aug.26,1968

21 AppLNo: 755,443

[73] Assignee:

[30] Foreign Application Priority Data Sept. 4, 1967 Germany ..P 15 69 606.7

[51] Int. Cl. ..C07d 87/50 [58] Field of Search ..260/244 R, 242, 326.5 B, 313.1

[56] References Cited 7 UNITED STATES PATENTS 3,299,092 1/1967 Brack ..260/326.5 B 3,347,865 10/1967 Brack et al.. ....260/3 1 3.1 3,362,953 1/1968 Brack ..260/313.l

FOREIGN PATENTS OR APPLICATIONS 1,388,597 12/1964 France ..260/326.5 B

730,088 5/1955 Great Britain ..260/326.5 B

OTHER PUBLICATIONS Chem. Abst, V01. 63, column 15021 (1965)QD1.A51

Primary Examiner-Natalie Trousof I Attorney-Plumley, Tyner & Sandt 57 ABSTRACT Basic dyestuffs of the formula v A I RN. C@N/ are suitable for the dyeing, printing and bulk dyeing of synthetic and semisynthetic materials especially polyamides,

acetate rayon and acid modified polyesters, leather, cocoafibers, paper and jute, for the production of inks and paste for ball point pens, for use in offset printing, for use in dyeing,

. printing and bulk dyeing materials which completely or predominately consist of polymerized acrylonitrile and or vinylidene cyanide, the dyeings and prints on the last mentioned materials are characterized by outstanding fastness properties, especially fastness to light, wet processing, cross dyeing, decatizing, sublimation, exhaust fumes and rubbing. The dyestuffs are readily soluble, they yield deep dyeings, due to their high yield and very good drawing power and they do not soil wool. In the formula given above A denotes the residual members of a heterocyclic five or six membered ring to which further rings may be annelated, R is hydrogen, alkyl aralkyl, cycloalkyl or aryl, and R may also be linked to A or to another ring which is annelated to the ring containing A, R is hydrogen, alkyl, aralkyl, cycloalkyl or aryl and R may also be linked to B or 8,, and X is an anion.

12 Claims, No Drawings NAPHTHOLACTAM-(l ,8) BASIC DYESTUFFS The object of the present invention comprises new basic dyestuffs of the formula (I) and a process for their production, which is characterized in that compounds of the formula (II) are reacted with phenoxazine derivatives of the formula (III) with the use of a condensation agent which yields an anion X.

In the formulae (I), (II) and (III), A denotes the residual members of a heterocyclic 5- or 6-membered ring to which further rings may be anellated; R is hydrogen, an alkyl, aralkyl, cycloalkyl or aryl radical, and R may also be linked to A or to another ring which is anellated to a ring containing A; R is hydrogen, an alkyl, aralkyl, cycloalkyl or aryl radical, and R may also be linked to B or B and X is an anion.

The radicals A, R and R,, the rings B and B and any rings anellated to the ring containing A may contain non-ionic substituents, but at least one of the two positions 3 and 7 in the rings B and B must be unsubstituted. Compounds of the formula (II) which are suitable for carrying out the claimed process are, for example, naphtholactam-( I ,8), N-methyl-, N- ethyl-, N-n-propyl-, N-isobutyl-, N-n-amyl-, N-n-hexyl-, N- phenyl-, N-4'-methylphenyl-, N-4-methoxyphenyl-, N-4- ethoxyphenyl-, N-benzyl-, N-4-methylbenzyl-, N-4'- chlorobenzyl-, N-4'-methoxybenzyl-, N-n-phenylethyL, N- cyclohexyl N-methoxycarbonylmethyl-, N-ethoxycarbonylmethyl-, N-'/3-chloroethyl-, N-B-bromoethyl-, N-B cyanoethyl- N-B-hydroxyethyb, N-B-dimethylaminoethyl-,' N-B- diethylaminethyl-, N-fi-methoxyethyl-, N- -ethoxyethyland N,2-trimethylene-naptholactam-(1,8); derivatives of these naphtholactams, which are substituted in the naphthalene nucleus, such as Nmethyl-4-chloro-, N-methyl-4-bromo-, N- ethyl-4-chloro- N-ethyl-4-bromo-, 4-chloro (and -bromo)- N,2-trimethylene-, N-ethyl-2,4-dichloroand -dibromo-, N- methyl-4-methoxyand -ethoxy-, N-ethyl-4-methoxyand ethoxy, N-methyland N-ethyl-4-acetyl-, N-methyland N- ethyl-4-amino-, N-me'thyland N-ethyl-4-acetylamino-, N- methyland N-ethyl-4-dimethylamino-, 2-ethyl-, 2-isopropyl-, N-methyI-Z-ethyland N-methy]-2-isopropyl-naphtholactam- 1,8; N-methyl-Z-pyridone, N-ethyl-Z-pyridone, N,6-dimethyl- 2pyridone, N,4-dimethyl-2-pyridone, N-methyl-4-chloro-2- pyridone, N-methyl-4-methoxy-2-pyridone, N-methyl-4-phenyl-Z-pyridone, N-methyl-4-benzyl-Z-pyridone, N-methyl-6- benzyl-2-pyridone, -pyridone, N-methyl-4-acetyl-2-pyridone, N-methyl-4-benzoyl-2-pyridone, N-benzyl-2-pyridone and N- phenyl 2-pyridone; 2-quinolone, N-methyl-, N-ethyland N- benzyl-2-quinolone, N-methyl-5-chloro-, N-methyl-5-bromo-, N-methyl-5-methoxy-, N-methyl-5-ethoxy-, N-methyl-S- methyl-, N-methyl-6-chloro-, N-methyl-6-methoxy-, N- methyl- 6-methyl-,'N-methyl-8-methoxyand N-methyl-8- bromo-Z-quinolone; the isomeric benzoquinolones and their N-methyl and N-ethyl derivatives; iso-quinolone-(I), N- methyl-, N-ethyl-, N-benzyland N-phenyl-isoquinolone-( l 6-methoxy- (and -ethoxy),-isoquinolone-( I 6-methyl( and 8- methyl)-isoquinolone-(l) and "the isomeric benzo-isoquinolones-( l 9-phenanthridone, N-methyl-, N-ethyl-, 3-bromo-, 3-chloro-, 3-acetylamino-, 3-dirnethylamino-, 3-methoxy-, N-

azinone-( 3) [formula (V)] and its 7-nitro-, 5,6,8-trichloroand 6,7-henzo derivatives:

2,3-dimethyl-indolone-(2) [formula (VI)], l,3,3-trimethyl-, l-ethyl-3,3-dimethyl-, l-phenyI-3 ,3-dimethyI-, l-benzyl-3 ,3- dimethyl-, l,3,3-trimethyl-5-chloro-, -5 bromo-, -5-methoxy-,

-5-ethoxyand -5-methoxycarbonyl-indolone-(2); 1-ethyI-4,5-

benzoand 1-niethyl-6,7-benzo-indolone-(2); thecompounds of the formulae (VII) to (XVI) R hydrogen (VII): R, (VIII): R hydrogen, R, methyl (IX): R hydrogen, R ethyl (X): R chlorine, R hydrogen (XI): R chlorine, R methyl (XII): R chlorine, R ethyl (XIII): R, bromine, Ra hydrogen (XV): R, bromine, R ethyl (XIV): R2= bromine, R =methyl (XVI): R methyl, R hydrogen;

the compounds of the formulas (XVII) to (XXIII) R5\ /Rt 0 N-R4 C (XVII):

(XVIII): R methyl, R R hydrogen (XIX): R ethyl, R R hydrogen (XX); R n-butyl, R R hydrogen (XXI): R iso-butyl, R R hydrogen (XXII): R hydrogen, R, R methyl (XXIII): F r= q= yk I l-methyl-3-ethylbenzimitfazolone, 1,3-diethyl-benzimidazolone, l-benzyl-3- methylbenzimidazolone, l-phenyl-3-methyl benzimidazolone, l ,3,5-trimethyl-, 1 ,3-dimethyl-5-methoxy-, l ,3-dimethyl-6- methoxy-, l,3-dimethyl-5,6-dimethoxy-, 1,3-dimethyl-5- chloro-, l,3-dimethyl-5-bromo-, I,3-dimethyl-5,6-dibromm and the isomeric naphthimidazolones-(Z); permidone, lrnethyl-perimidone, pyrimidone-(Z), l-methybpyrimidonc- (2) and S-phenylpyrimidone-(Z), benzothiazolone-(Z) and N- methyl-benzothiazolone-(Z).

Suitable compounds of the formula (III). are, for example, phenoxazine, N-methyl-, N-ethyl-, N-B-cyanoethyl; N-flhydroxyethyI-, N-n-propyl, N-n-butyl-, N-iso-butyl-, N-isoamyl-, N-n-hexyl-, N-benzyl-, N,4-methylbenzyl, N-4- chlorobenzyl, N-4-methoxy-(ethoxy)-benzyl-, N-phenyland N-4-nitrophenyl-phenoxazine and nuclear substitution products, such as l-ethyl-, l,9-diethyl-, l-isopro'pyl-, l-nitro-, l-nitro-3-chloro-, 3-methoxy-, 3-ethoxy-, 3-methyl-, 3- acetylamino-, 3-dimethylamino-, 2-methoxycarbonyl-, N- methyl-3-chloro(or -bromo)-, N-methyl-3-methoxy(or -ethoxy)-, N-methyl-3-acetyl-, N-methyl-3,6-dichloro-, N-methyl- 2,8-dibromo-, N-methyl-2,4-dichloro-, N-ethyl-3-acetyl-, N- ethyl-3-cyano-, N-methyl-l-fluoroand N-methyl-3- acetylaminophenoxazine.

Suitable condensation agents, are, for example, acid chlorides, such as phosphorus oxychloride, phosphorus trichloride, phosphorus oxybromide, phosphorus tribromide, thionyl chloride and phosgene, Friedel-Crafts catalysts, such as tin(IV) chloride and titanium (IV) chloride, as well as mixtures of these compounds with one another and/or with aluminum chloride, zinc chloride; iron(III) chloride and/or phosphorus pentoxide.

Preferred dyestuffs are those of the formulae in which R, R and X have the same meaning as above and R, and R stand for lower alkyl radicals and in which the radicals the quinoline, isoquinoline and indolenine system may contain further non-ionic substituems.

To carry out the process, a compound of the formula (II) is heated with the equivalent amount of a compound of the formula (III) and one of the condensation agents mentioned above, preferably with phosphorus oxychloride, to 40 to 150 C, preferably 50 to C (boiling-point of the phosphorus oxychloride). It is also possible to use deficient or excess amounts of the compound (Ill). Furthermore, it is frequently of advantage, to add an inert diluent, such as methylene chloride, chloroform, carbon tetrachloride, benzene, toluene, chlorobenzene, dichlorobenzene, nitrobenzene, .cyclohexane, methyl-cyclohexane or paraffin oil. In many cases, an excess of phosphorus oxychloride can, at thersame. time, serve as diluent. Thedyestuffs of the formula (I) thus formed are isolated in the usual manner, for example, by filtering off with suction and washing with benzene or by removing the diluent by steam distillationand subsequently salting out the resulting aqueous dyestuff solution.

Dyestuffs of the formula (I) in which R stands for hydrogen, can be converted, by treatment with acid-binding agents, such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, milk of lime, ammonia and organic amines, into the dyestuff bases of the formula (XXIV) from which they are derived.

XXIV

In the formula (XXIV), A and R, have the same meaning as above; A and R as well as the rings B and B, and any rings anellated to the ring containing A may carry non-ionic substituents.

Dyestuffs of the formula (I), in which R, stands for hydrogen and R for an alkyl, aralkyl, cycloalkyl or aryl radical, can be converted, by treatment with acid-binding agents, such as sodium hydroxide, potassium hydroxide, sodium carbonate,-

potassium carbonate, milk of lime, ammonia and organic amines, into the dyestuff bases of the formula (XXV) from which they are derived.

0 B1 7 xxv ethyl) ester, chloro (or bromo)-acetic acid, methyl (or ethyl) ester, benzyl chloride, B-chloropropionitrile or ethylenechlorohydrin.

In general, the type of the anion X contained in the dyestuffs (I) is unimportant for their dyeing properties and it is determined by the process of production and by the purification of the crude dyestuff which may have been carried out. In general, the dyestuffs are present as halides, especially chlorides or bromides, or as methosulphates, ethosulphates, sulphates, benzeneor toluene-sulphonates or acetates. These anions may be exchanged in any way for other anions, such as tetrafluoroborate, phosphate, chloro'zincate, nitrate, perchlorate, oxalate, propionate, formate, citrate, maleinate, malate, tartrate, lactate or benzoate ions.

The dyestufi's which can be obtained according to the invention are new. They are suitable for the dyeing, printing and Lud bulkdyeing of synthetic and semi-synthetic materials, for example, polyamides, acetate rayon and acid-modified aromatic polyesters, of leather, coco fibers, paper and jute, for the production of inks and pastes for ball point pens, for the use in offset printing, but primarily for the dyeing, printing and bulkdyeing (mass-dyeing) of materials which completely or predominantly consist of polymerized acrylonitrile and/or vinylidene cyanide. The dyeings and prints on the last-mentioned materials are characterized by outstanding fastness properties, especially fastness to light, wet processing, crossdyeing, decatizing, sublimation, exhaust fumes and rubbing. The dyestuffs are readily soluble, they yield deep dyeings, due to their high yield and very good drawing power, and they do not soil wool.

Dyestuffs of the formula (1) in which A stands for the residual members of a benzo-(c,d)-indole derivative, are particularly valuable for industrial purposes. In addition to their outstanding fastness properties, they are characterized by an unusual long-wave absorption and, therefore, enable greenblue to green dyeings of great depth of color to be produced, such as have hitherto not been obtainable with equivalent fastness properties. These dyeings also have a very good so-called evening color", i.e., their shade does not appear to be changed in an undesirable manner in artificial light.

The parts given in the following Examples are parts by weight.

EXAMPLE 1 59 Parts N-methyl-phenoxazine and 51 parts naphtholactam-( 1,8) areheated in 500 to 750 parts chlorobenzene with 50 to 100 parts phosphorus oxychloride at 80 to 90 C for 24 hours. After cooling, the precipitated crystalline dyestuff of the formula =?-@-r Q (i) i is filtered off with suction and washed with benzene. 95 Parts are obtained; a further. fraction can be obtained by working up the filtrate. For conversion into the dyestuff base, the dyestuff salt obtained is stirred with an excess of a strongly diluted sodium carbonate solution at about 60 C for a short time. The resultant base is filtered off with suction, washed with water and dried over potassium hydroxide. lt corresponds to the formula heated at boiling temperature for one-half to 1 hour, allowed to cool, the precipitated dyestuff of the formula is filtered off. with suction and washedwith toluene or benzene. The yield is almost quantitative.

The toluene can be replaced with another solvent which is inert towards dimethyl sulphate, such as chlorobenzene or 1 ,2-dichlorobenzene.

The dyestuff so obtained yields very strongly greenish blue dyeings and prints of outstanding fastness properties on materials consisting completely or predominantly of polyacrylonitrileand/or vinylidene cyanide.

A very similar dyestuff is obtained when the dimethyl sulphate is replaced with the equivalent amount of diethyl sulphate. The N-methyl-phenoxazine was prepared according to the process described by Miiller, Buu-l-loi and Rips, J .-Org. Chem. 24, page 37.

EXAMPLE 2 19.7 Parts N-ethyl-naphtholactam-( 1,8) and 19.7. parts N- methyl-phen'oxazine are stirred with 100 parts phosphorus oxychloride at 70 -90 C for 10 to hours. After this period of time, the excess phosphorus oxychlorideis decomposed by pouring the reaction mixture into water, and the precipitation of the resultant dyestuff of the formula 25 50 parts of phosphorus oxychloride. After cooling the precipitated crystalline dyestuff is filtered off with suction,

washed with benzene or toluene and then recrystallized from water. The crystallizate contains a blue dyestuff which is formed as a by-product and which is separated off by washing with water. There is obtained a dyestuff of the formula which dyes materials of polyacrylonitrile in green shades of very good fastness properties. Similar valuable green dyestuffs are obtained when using, instead of 4-bromo-N-ethylnaphtholactam, an equivalent quantity of 4-chloro-N-ethylnaphtholactam-( 1 ,8), 4-chloroN-n-propylnaphtholactam- 1,8) or 4-bromoN-mpropyl-naphtholactam-( 1,8). Some species of dyestuffs within the present invention are as follows CH3 ('i') I I O3 I \o CH3 X t OH in which R is hydrogen, alkyl with 1-6 carbon atoms; alkyl with l6 carbon' atoms substituted with diethylamino, dimethylamino, ethoxycarbonyl, methoxycarbonyl, chloro, bromo, cyano, hydroxy, methoxy, or ethoxy; phenyl; phenyl' substituted with methyl, methoxy, or ethoxy; phenyl lower alkyl; phenyl lower alkyl substituted with methyl, methoxy or chloro; or cyclohexyl; R is hydrogen or a nonionic substituent selected from the group consisting of chloro, bromo, methoxy, ethoxy, acetyl, amino, acetylamino ordimethylamino; R" is hydrogen or a nonionic substituent selected from the group consisting of chloro, bromo, ethyl or propyl', and wherein R and R" may together by trimethylene; R is hydrogen or a substituent selected from the group consisting of alkyl with l6 carbon atoms; ethyl substituted with cyano or hydroxy; phenyl; nitro-phenyl; benzyl; 'benzyl substituted with methyl; chloro, methoxy or ethoxy R, is methyl, ethyl, propyl, fluoro, chloro, bromo, nitro, cyano, methoxy, ethoxy, acetyl, acetylamino, dimethylamino, or methoxycarbonyl;

m is a number from 0-2; and

X represents an anion.

EXAMPLE 4 When carrying out the process described in Example 3, using, however, the starting products given in the Table below, new dyestuffs of very good fastnessproperties are likewise obtained.

Starting Starting product ll product ll] Shade N-methyl-4-methoxy- I N-methylblue green naphtholactam-( 1,8): phenoxazine' N-m'ethyl-4-ethoxy- N-methylblue green 4 nuphtholuctum-( l ,8) phenoxuzine Nethyl-d-ucetumino- N-methylgreen naphtholactam-( L8) phenoxazine N-ethyl-4-dimeth'ylamino- N-methylgreen naphtholactam-( 1,8) *phenoxazine N-ethyl4-rnethyl- N-rnethylstrong naphth0lactam-( 1,8) phen'oxazine greenish blue Z-ethyl-naphtholactam- N-methylstrong 1,8) phenoxazine greenish. blue 2 -ethyl-N-methyl- N-methylgreenish blue naphtholactam-( 1,8) phenoxazine 1 N-ethyl-naphtholactam- N-ethylvery strong 1,8) phenoxazine greenish blue N-B-cyanoethylphenoxazine N-ethyl-naphtholactaml ,8)

greenish blue 82 Parts N-methyl-benzthiazolone-(Z) and l 10 parts N- methyl-phenoxazine are heated to about C for 6 to 8 hours together with 150 to 200 parts phosphorus oxychloride. After cooling the mixture is stirred with 5,000 parts of water. The reaction mixture is filtered off with suction at about 30 C; the residue is recrystallized from 700 to 1,000 parts of water with the addition of charcoal. The precipitation of the dyestuff of the formula CH is completed by adding dropwise ml'of a saturated NaCl solution. The dyestuff yields red orange dyeings and prints on materials of polyacrylonitrile and acetate rayon.

When carrying out the afore-described process using, however, an equivalent amount of l,3,3-trimethyl-indolone-(2) instead of benzthiazolone, there is obtained the red dyestuff of the formula The dyes and prints obtained with the red dyestuTf on materials of polyacrylonitrile are distinguished by very good -fastness properties.

" EXAMPLE 6 60 Parts 2,8,IO-trimethyl-phenoxazine and 54 parts N- ethyl-naphtholactam-( 1,8) are heated with 20 to 40 parts 1,2- dichlorobenzene and 10 to'2O parts phosphorus oxychloride to about 90 C for 20 hours. After cooling the dichlorobenzene is driven off with steam and the remaining aqueous solution is treated with sodium chloride until the resulting dyestuff is completely precipitated. The resinous crude product thus obtained is purified by recrystallization from water with the addition of charcoal. There is obtained a dyestuff of the formula which dyes materials of polyacrylonitrile in very strong greenish blue shades of very good fastness properties.

The 2,8,lo-trimethyl-phenoxazine used in the above process was prepared as follows:

635 Parts 2,8-dimethyl-phenoxaz'ine and 4,500 parts methanol were heated to 280 to 290 C for hours with the addition of parts of phosphorus trichloride. A pressure of about 155 atm. resulted. After cooling the solution was neutralized with a methanolic caustic potash solution. The methanol was distilled off, the oily residue washed with warm water, dried and distilled. The N-methyl-derivative boils at 182 C to 185 C and 1.3 mm Hg. Yield: 242 parts.

I claim:

1. Dyestuff of the formula in which R is hydrogen, alkyl with 1-6 carbon atoms; alkyl with 1-6 carbon atoms substituted with diethylamino, dimethylamino, ethoxycarbonyl, methoxycarbonyl, chloro, bromo, cyano, hydroxy, methoxy, or ethoxy; phenyl; phenyl substituted with methyl, methoxy, or ethoxy; phenyl lower alkyl; phenyl lower alkyl substituted with methyl, methoxy or chloro; or cyclohexyl; R is hydrogen or a nonionic substituent selected from the group consisting of chloro, bromo, methoxy, ethoxy, acetyl, amino, acetylamino or dimethalamino; R" is hydrogen or a nonionic substituent selected from the group consisting of chloro, bromo, ethyl or isopropyl; and wherein R and R may together be trimethylene; R, is hydrogen or a substituent selected from the group consisting of alkyl with l6 carbon atoms; ethyl substituted with cyano or hydroxy; phenyl; nitro-phenyl; benzyl; benzyl substituted with methyl, chloro, methoxy or ethoxy R is methyl, ethyl, isopropyl, fluoro, chloro, bromo, nitro, cyano, methoxy, ethoxy, acetyl, acetylamino, dimethylamino, or methoxycarbonyl;

m is a number from 02; and

X represents an anion.

2. A dyestuff of claim 1 of the formula in which X is an anion.

- 4. A dyostuff of claim 1 of the formula in which X is an anion.

5. A dyestuif of claim in which X is an anion.

6. A dyestuff of claim 1 of the formula in which X is an anion.

8'. A dycstuff of claim 1 of the for mula in which X is an anion.

9. A dyestuff of claim 1 of the formula in which X is an anion.

10. A dyestuif of claim.

in which X is an anion.

1 of the formula 11. A dynstuff of claim 1 of the formula CH in which X is an anion.

in which X is an anion.

12. A dyustuff of claim 1 0f the formula m UNITED STATES PA' IENT OFFICE CERTIFICATE OF CORRECTION June 27, 1972 Patent No. r 3, 73,132 I Dated Inventor(s) Alfred Brack It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

COLUMN LINE ERRQR l 43 "n--" should read -B Q 2 a 21 "2,3" should read -3,3-.-..

7 2nd formu-laT Y -CH should read --CH 2nd Column of table the word "phenoxazine" 1s missing 9 33 "dimethalamino" should read -dimethylamino-.--.

12 Claim 12 in the formula "-HC should read -CH Signed and sealed this 3rd dayv of December 1974.

(SEAL) Attest:

c. MARSHALL DANN' McCOY M. GIBSON 'JR;

Commissioner of Patents Attesting Officer FORM po-wso (to-s9) USCOMM-DC 60376-P69 U.S. GOVERNMENT PRINTING OFFICE I919 0-366-334 

2. A dyestuff of claim 1 of the formula 